That would depend on your definition of "stationary". If it is a direct wire, no plug, then yes, it should be on it's own circuit. But the truth is that if you know the max load of a piece of equipment and size both wire and breaker as such you are protected. If another machine is on that same circuit and both run exceeding the amp load then the breaker will trip. If it's borderline then things like starting both at the same time will have an effect as well as you get higher starting amps initially then usually go down to run load amps which is different than rated amps. Common sense says to size breakers and wire to rated amps and seperate the loads. For me, I have a 220V circuit that can run either the Sawstop or the 8" jointer. Both have the appropriate plug and both can be plugged in at anytime as there are 3 outlets in various places in the shop. Only one can run at a time less it trips the breaker which is how it is intended. If this were a multi person shop I'd wire a bit differently but is isn't and won't be as long as I'm here. I also have all outlets numbered according to the breaker number so if you need to work on a circuit, like replacing an outlet, you know which breaker to turn off but take my word on this if nothing else, always check with a voltmeter before continuing. I've had my share of shocking surprises. And if your dealing with 3 phase check all legs to ground. I've had disconnects where the blades didn't all disconnect with the throw of the handle, surprise.Chuck, those codes can be different from one jurisdiction to another, here in the US. Where I am in rural AZ, there's nothing except common sense to prevent wiring several machines to one circuit. The inspector who signed off on my shop wiring job never even asked. And, a couple stationary machine were in place when he did the inspection.
But always check with local and national electrical codes. Inspectors are not responsible for their mistakes. I've seen stuff passed that was totally wrong and dangerous. If you don't know, higher an electrician.